In recent years, increasingly sophisticated telematics systems have been developed to detect an emergency condition or activation, and in response, initiate a call to a call center. Systems have been developed for monitoring fixed customer premises locations or personnel at specific site as well as for vehicle applications. For motor vehicle applications, for example, an on-board system monitors one or more sensors to determine when a crash or other emergency has occurred. Upon detecting an emergency condition, such as a crash, the on-board system activates a cellular transceiver to initiate a cellular telephone call to a call center of the telematics service provider (TSP). Upon connection to the call center, the system may communicate certain data, such as location determined by global positioning satellite (GPS) processing, identification data and crash related data. After the data transmission, the call is converted to a voice call in which a TSP representative at the call center can attempt voice communication with an occupant of the vehicle. The TSP also offers mechanisms for the representative to contact emergency service personnel in the area, to respond appropriately to the incident.
For mobile applications in vehicles, the primary communication resource is a cellular transceiver for communications via a public mobile wireless communication network, typically operated by a mobile service provider or carrier. Even some fixed location installations may utilize communications through a mobile service provider's network because the service is less likely to be interrupted by events that might otherwise damage landline network facilities at the location.
Typically, the telematics customer subscribes to the telematics service from a telematics service provider TSP. The TSP in turn contracts with a wireless service provider or carrier, so that the customer's telematics unit at the location or in the vehicle is active for wireless communication via the wireless carrier's mobile network. With respect to the communication service through the mobile network, the TSP is essentially a reseller of the carrier's wireless communication service. The customer's service will be active with respect to the TSP and the system or systems operated by the TSP. However, the customer's telematics unit also must also be active with respect to the carrier's wireless communication service through the mobile network, in essentially the same way as a mobile station of a regular subscriber to the carrier's wireless communication services.
Currently mobile or wireless devices on active accounts with the wireless carrier register on the mobile network and take up resources on the switching and signaling infrastructure of the network. The devices signal to/from network elements, to indicate current point of attachment and for station and/or user authentication.
With a normal mobile station, once its deactivated, the user will typically throw it away or at least will power it down and stow it away (e.g. for later use as a spare). In either case, the old mobile station is no longer operational and therefore does not attempt signaling/registration with the mobile network. Also, the mobile number(s) assigned to the station are assigned to another mobile station. A telematics device, particularly one for a vehicle application, typically remains installed and may remain powered and operational, even though the TSP and/or the wireless network may no longer recognize the device for purposes of providing services to the telematics unit. Today, telematics devices that have been deactivated by the TSP remain in the mobile network for an undetermined length of time with no automatic termination. For example, such devices continue to attempt signaling or registration communications with the network.
Currently mobile or wireless devices on active accounts with the wireless carrier are assigned one or more numbers for device authentication and related signaling purposes. Typically, a mobile station is assigned a mobile directory number (MDN) and a mobile identification number (MIN). The MDN is an actual telephone number. The MIN has a telephone number format but is typically a second number assigned to the device only for signaling purposes. At least the MIN and usually the MDN are programmed into the subscriber's mobile station, as part of the process of provisioning the device for operation through the wireless network. Association of those numbers with the subscriber and the subscriber's mobile station are also recorded in various databases used for service control, billing and the like in or otherwise associated with the wireless network. These numbers, particularly the MDNs, are resources available to the carrier on a limited basis. When a mobile station is deactivated, the carrier recovers the numbers for reuse, e.g. assignment to a different mobile station. In a typical deactivation procedure, e.g. when the subscriber replaces a mobile station with a new one, the carrier will delete the MDN and MIN from storage in the old mobile device.
As noted earlier, telematics devices that have been deactivated by the TSP often remain in the mobile network for an undetermined length of time with no automatic termination. For example, the units still retain any MDN or MIN numbers in storage. This is particularly troublesome in terms of inventory of mobile directory numbers (MDNs), because the inactive telematics unit is still provisioned on the wireless network, e.g. it still has a MDN assigned to it. Since the MDN is a particularly scarce resource, it is problematic in that the carrier can not re-assign the MDN to another mobile station or telematics unit.
Hence, a need exists for a technique and/or equipment to automatically deactivated telematics unit with respect to the wireless network, when such a device is inactive with respect to the telematics service. Such an automatic termination technique should enable the wireless service provider to recover MDNs or the like from the inactive devices. It would also be desirable for the automatic deactivation to stop the inactive telematics unit from signaling the wireless network, e.g. to reduce signaling traffic load on the network. However, it may be desirable to leave the telematics unit with some residual functionality, e.g. to allow some limited form of emergency call such as to 911.